Abstract
Annealed low-temperature-grown GaAs was studied by time-resolved photoreflectance measurement at well-above-bandgap photon energies and by photoreflectance as well as transmission measurements at near-bandedge wavelength. At near-bandedge wavelength, the initial changes in reflectivity and transmission were observed to relax at identical relaxation rate, which was attributed to the absence of carrier cooling and the domination of carrier trapping. All the measured photoreflectance traces were found to be well fitted by the previously proposed three-component decomposition procedure. Among the three components, the fast positive peak was attributed to absorption bleaching and its relaxation, that is, the scattering of the photo-carrier out of their initially excited states by carrier cooling and trapping. The decay times of the positive peak, combined with the carrier cooling times extracted from photoreflectance measurement on semi-insulating GaAs, give consistent estimate of carrier trapping time at all wavelengths within the spectral range. Our results verify that well-above-bandgap photoreflectance measurement combined with the three-component fitting procedure can be used to estimate the photo-carrier trapping time which are consistent with that obtained by near-bandedge photoreflectance and transmission techniques.
Similar content being viewed by others
References
Bennett, B.R., R.A. Soref and J.A. Del Alamo. IEEE J. Quantum Electron. 26 113, 1990.
Dykaar, D.R., D.J. Eaglesham, U.D. Keil, B.I. Greene, P.N. Saeta, L.N. Pfeiffer, R.F. Kopf, S.B. Darack and K.W. West. Mater. Res. Soc. Symp. Proc. 241 245, 1992.
Gupta, S., M.Y. Frankel, J.A. Valdmanis, J.F. Whitaker, G.A. Mourou, F.W. Smith and A.R. Calawa. Appl. Phys. Lett. 59 3276, 1991.
Gupta, S., J.F. Whitaker and G.A. Mourou. IEEE J. Quantum Electron. 28 2464, 1992.
Harmon, E.S., M.R. Melloch, J.M. Woodall, D.D. Nolte, N. Otsuka and C.L. Chang. Appl. Phys. Lett. 63 2248, 1993.
Kaminska, M., Z. Liliental-Weber, E.R. Weber, T. George, J.B. Kortright, F.W. Smith, B-Y. Tsaur and A.R. Calawa. Appl. Phys. Lett. 54 1881, 1989.
Liliental-Weber, Z., H.J. Cheng, S. Gupta, J. Whitaker, K. Nichols and F.W. Smith. J. Electron. Mater. 22 1465, 1993.
Lin, W.Z., J.G. Fujimoto, E.P. Ippen and R.A. Logan. Appl. Phys. Lett. 50 124, 1987.
Lochtefeld, A.J., M.R. Melloch, J.C.P. Chang and E.S. Harmon. Appl. Phys. Lett. 69 1465, 1996.
Mclntosh, K.A., K.B. Nichols, S. Verghese and E.R. Brown. Appl. Phys. Lett. 70 354, 1997.
Prabhu, S.S., S.E. Ralph, M.R. Melloch and E.S. Harmon. Appl. Phys. Lett. 70 2419, 1997.
Siegner, U., R. Fluck, G. Zhang and U. Keller. Appl. Phys. Lett. 69 2566, 1996.
Yablonovitch, E., D.M. Hwang, T.J. Gmitter, L.T. Florez and J.P. Harbison. Appl. Phys. Lett. 56 2419, 1990.
Yu, J.S., H.C. Ho, S.F. Horng and C.C. Chi. Jpn. J. Appl. Phys. 36 2144, 1997a.
Yu, J.S., Y.S. Chang, J.N. Chen, T.R. Tsai, S.F. Horng and C.C. Chi. J. Chinese Institute of Electrical Engineering. 4 185, 1997.
Yu, J.S., S.F. Horng and C.C. Chi. Jpn. J. Appl. Phys. 37 554, (1998).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Horng, SF., Lu, SH., Yu, JS. et al. Comparison of optical pump-probe characterization of low-temperature-grown GaAs at well-above-bandgap and near-bandedge wavelengths. Optical and Quantum Electronics 32, 573–584 (2000). https://doi.org/10.1023/A:1007008003089
Issue Date:
DOI: https://doi.org/10.1023/A:1007008003089